1. Technical Field
The present invention relates to an optical disk inspecting apparatus and method for inspecting presence or absence of a defect in an optical disk.
2. Related Art
Optical disks have been widely known which can irradiate laser light and thereby record or reproduce data; and when there is a flaw or the like on the recording surface of these optical disks, it may be difficult to reproduce data. Accordingly, when an optical disk is lent or sold, presence or absence of a defect such as a flaw on the recording surface must be preliminarily inspected. Particularly, in optical disk rental shops and secondhand disk shops where the quality of optical disk is difficult to ensure, such inspection is highly needed. Thus, many apparatuses for inspecting an optical disk have hitherto been proposed (for example, JP 2005-243099 A and JP 10-21548 A).
Here, in inspecting an optical disk, determination is ordinarily made based on the reproduction quality or the like in reproducing the optical disk; but in order to shorten the reproduction time (inspection time) for this inspection, the optical disk may be played at a high speed (for example, speed 24 times as high). However, problems caused by a flaw on the recording surface rarely occur at a high speed, but are more likely to occur at a low speed. Accordingly, an optical disk determined to be flawless in high-speed reproduction may not be played normally in low-speed (the same speed) reproduction. In order to avoid this problem, according to related art, an optical disk is played at a low speed over the whole surface to inspect for presence or absence of a defect in the optical disk. In this case, there arises a problem that it takes a long time to inspect the optical disk.
Thus, it is an advantage of the present invention to provide an inspecting apparatus and method which can more quickly detect presence or absence of a defect in an optical disk.